Pope Francis has called on the world’s rich nations to begin paying their “grave social debt” to the poor and take concrete steps on climate change, saying failure to do so presents an undeniable risk to a “common home” that is beginning to resemble a “pile of filth”.

The pope’s 180-page encyclical on the environment, released on Thursday, is at its core a moral call for action on phasing out the use of fossil fuels.

But it is also a document infused with an activist anger and concern for the poor, casting blame on the indifference of the powerful in the face of certain evidence that humanity is at risk following 200 years of misuse of resources.

Up to now, he says, the world has accepted a “cheerful recklessness” in its approach to the issue, lacking the will to change habits for the good of the Earth.

“Climate change is a global problem with grave implications: environmental, social, economic, political and for the distribution of goods,” the papal statement says. “It represents one of the principal challenges facing humanity in our day.”

The release of the statement was timed with the pope’s upcoming trip to the US, where he will speak before the United Nations and a joint session of the Congress.

“This is his signature teaching,” said Austen Ivereigh, who has written a biography of the pope. “Francis has made it not just safe to be Catholic and green; he’s made it obligatory.”

Ivereign added: “It captures his deep disquiet about the direction of the modern world, the way technology and the myth of progress are leading us to commodify human beings and exploit nature. This comes right out of his soul.”

The encyclical, which can now be considered the church’s official position on the environment, includes practical guidance. Pope Francis rejects “simple solutions” to climate change such as cap and trade systems, which he says give rise to harmful speculation. He also dismisses any suggestion that population increases harm to the environment and should therefore be controlled, and resists making any judgment on genetically modified foods.

The essay was released following months of intense speculation about how far the pontiff would delve into a scientific realm that, depsite the overwhelming agreement of scientists, is still considered controversial in some countries such as the US, where views on climate change are divided along political lines.

Cardinal Peter Turkson, the pope’s top official on social and justice issues, flatly rejected arguments by some conservative politicians in the US that the pope ought to stay out of science.

“Saying that a pope shouldn’t deal with science sounds strange since science is a public domain. It is a subject matter that anyone can get in to,” Turkson said at a press conference on Thursday.

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In an apparent reference to comments by Republican presidential contender Jeb Bush, who said he did not take economic advice from the pope, Turkson said that politicians had the right to disregard Francis’s statement, but said it was wrong to do so based on the fact that the pope was not a scientist.

“For some time now it has been the attempt of the whole world to kind of try to de-emphasise the artificial split between religion and public life … as if religion plays no role,” he said. Then, quoting an earlier pope, he said the best position was to “encourage dialogue between faith and reason”.

“Reason does have blind spots, but at the same time, reason can also challenge religion to become practical,” he said.

Francis, who was elected in 2013 and has put social justice and reform of the church at the heart of his papacy, said on Thursday that his text should not be read as a green manifesto, but instead as a social teaching.

“The foreign debt of poor countries has become a way of controlling them, yet this is not the case where ecological debt is concerned,” Francis wrote. “In different ways, developing countries, where the most important reserves of the biosphere are found, continue to fuel the development of richer countries at the cost of their own present and future.

“The developed countries ought to help pay this debt by significantly limiting their consumption of non-renewable energy and by assisting poorer countries to support policies and programmes of sustainable development.” The question now is whether the pope’s sweeping statement will shake-up climate talks.

Turkson said on Thursday that the pope considered it imperative that “practical proposals not be developed in an ideological, superficial or reductionist way”.

“For this, dialogue is essential,” he said.

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The release of the statement was timed with the pope’s upcoming trip to the US, where he will speak before the UN and seek to nudge climate change negotiators ahead of their December meeting in Paris. He will also speak before a joint session of the US Congress.

While much of the encyclical is a spiritual reflection on the biblical story of creation and humanity’s God-given role in caring for the Earth, both the statement and the presentation preceding it were infused with science, representing a rare locking of arms between the church and scientific community.

Hans Joachim Schellnhuber, a top climate scientist and scientific adviser to the Vatican, said the impact of global warming would be “abrupt, surprising, and irreversible”, and that it would shut down parts of the earth much in the same way that the body dies of a fever.

“The vital organ’s of the world’s body will collapse,” he said in opening remarks before a press conference.

The encyclical – a statement of papal teaching – describes an “ecological crisis” and includes a section devoted to the latest scientific findings. It argues that climate change is not just a “global problem with serious implications”, but has an impact felt disproportionately by the world’s poorest people.

Francis writes: “Those who possess more resources and economic or political power seem mostly to be concerned with masking the problems or concealing their symptoms”. The failure to respond, he says, points to the loss of a “sense of responsibility for our fellow men and women upon which all civil society is founded”.

The question now is whether the encyclical will shake-up the climate debate, as Francis clearly hopes it will.

“I really think it is a game-changer,” says Ivereigh, the papal biographer. “In asking Catholics to reshape the market by changing their consumer habits, it could release a whole new form of people power.”

The Argentinian pontiff heaps praise on efforts made by scientists to find solutions to man-made problems, and lashes out at those who intervene in the service of “finance and consumerism”.

“It is actually making our earth less rich and beautiful, even more limited and grey,” he says.

The pope did not speak at the press conference on Thursday, but earlier in the week he said he hoped his message would be received with an “open spirit”.

The pope has previously expressed disappointment over the lack of an effective global plan to tackle climate change. But he faces an uphill battle to convert those who doubt human influence.

Even among Catholics in the US, views on global warming are sharply divided along political lines. A recent survey by Pew Research showed that Catholic Republicans view the nearly universally accepted scientific facts with deep scepticism.

Overall, the survey found that 71% of US Catholics believe the earth is warming, and about half (47%) believe humans are the cause and that it is a serious problem.

But while eight in 10 Catholic Democrats say that there is solid evidence that global warming is real, only about half of Catholic Republicans agree. Far fewer – just one quarter of Catholic Republicans – believe that global warming is caused by humans.

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The UN climate chief, Christiana Figueres, said the church’s newly unveiled teaching on the environment underscored the “moral imperative for urgent action”.

“This clarion call should guide the world towards a strong and durable universal climate agreement in Paris at the end of this year,” she said in a statement. “Coupled with the economic imperative, the moral imperative leaves no doubt that we must act on climate change now.”

Jim Yong Kim, the World Bank president, agreed: “Today’s release … should serve as a stark reminder to all of us on the intrinsic link between climate change and poverty.”

He said the impact of climate change was most devastating for the “unacceptably high number of people living in extreme poverty”. Extreme weather events had taken the lives of more than 2.5 million people and resulted in $4tn in damages, he said.

“We must now seize this narrow window of opportunity and embark on ambitious actions and policies to help protect people and the environment,” he added.

Francis has been sending his encyclical to church officials around the world over the last few days, Federico Lombardi, the Holy See’s head of communications, said.

The pontiff included a personal handwritten note in his communication, ending with a plea for help: “United in the lord, and please do not forget to pray for me.”